list-attachments

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations, but description discloses it returns metadata only, not bytes. It is read-only in nature, though not explicitly stated as such.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Three concise sentences structured with usage context, return value, and exclusions. Slightly verbose but well-organized.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With output schema present, description covers all needed context: purpose, parameter prerequisite, and return summary (names, MIME types, sizes, count). No gaps.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The only parameter 'id' is explained as the message id, with guidance on how to obtain it. Despite 0% schema coverage, the description fully compensates.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the verb 'enumerating', the resource 'attachments' by message id, and outputs (names, MIME types, sizes, count). It distinguishes from siblings like fetch-attachment and save-attachment.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicitly states 'Use when' and 'Do not use when', directing to alternative tools for bytes and advising to obtain message id from search-messages or list-messages.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.